Automated storage and retrieval apparatus for freezers and related method thereof

ABSTRACT

An automated cold storage apparatus, and related method thereof, provides a sample process management system that is a revolutionary approach to the storage and retrieval regarding critical samples. The system—a significant technological breakthrough in laboratory automation—is the first ultra low temperature robotic system capable of being validated. Samples in containers are stored and retrieved robotically through an airlock climate-control chamber that is automatically dehumidified by a dry gas purge, such as a carbon dioxide or nitrogen purge or the like. This purge rapidly reduces ambient humidity to a desirable relative humidity (RH), e.g., less than about 15% RH, virtually eliminating the accumulation of frost. Microplates are systematically identified using barcode technology, for example. Once through the climate-controlled chamber, the containers (i.e., samples) are robotically transferred to the rotary mechanism. This mechanism transports the containers to a derived nest location upon the storage means, such as a carousel or to one of the stationary addresses.

RELATED APPLICATIONS

This application claims priority from U.S. Provisional ApplicationSerial No. 60/227,166, filed on Aug. 23, 2000, entitled “AutomatedStorage and Retrieval Apparatus for Freezers and Related MethodThereof,” and Ser. No. 60/299,597, filed on Jun. 20, 2001, entitled“Automated Storage and Retrieval Apparatus for Freezers and RelatedMethod Thereof,” the entire disclosures of which are hereby incorporatedby reference herein.

FIELD OF INVENTION

This invention relates to an automated storage and retrieval apparatusfor ultra low temperature freezers, and more particularly an apparatusthat improves the overall quality of the climate associated with storingitems therein.

BACKGROUND OF INVENTION

Advancements in biotechnology and medical science require the analysisof ever-increasing numbers of various biological samples. Manybiological samples must be stored at below-freezing temperatures inorder to preserve them for future reference, analysis, or use. Forexample, DNA, RNA, cells and protein samples, as well as the reagentsnecessary for conducting various analyses of these samples, must bestored at ultra-cold temperatures to prevent degradation that wouldinterfere with reliable analyses of the biological products.

Storage below −80° C. is generally required for successful preservationof biomolecules, cells, and tissue (morphology and viability) forextended periods of time. However, shelf life and the ability to recoverliving cells are dramatically improved at about −196° C. (−196° C. beingthe boiling point of liquid nitrogen). The National Institute ofStandards and Technology has suggested that the term cryogenics beapplied to all temperatures below −150° C. (−238° F. or 123° aboveabsolute zero on the Kelvin scale). Some scientists regard the normalboiling point of oxygen (−183° C. or −297° F.), as the upper limit. Theterm ultra low temperature is probably not officially recognized by anystandards body. However, it is generally agreed that a freezer refers toa storage device that operates from about−5° C. to −20° C., an ultra lowoperates from about −50° C. to about −90° C., and a cryogenic freezeroperates from about −140° C. to −196° C.

There are many problems associated with placement and retrieval ofsamples from ordinary laboratory freezer compartments. For instance, inan ordinary freezer compartment, containers of samples must be stored infront of and on top of each other to maximize use of the availablespace. Even if the containers are of standard sizes, and thereforeeasily stackable and even if a positional inventory of the samples iskept, it is still necessary to shuffle the containers around manually inorder to retrieve a desired container. This is problematic because itrequires keeping the freezer door open for possibly extended periods oftime. Keeping the freezer door open causes the interior temperature ofthe freezer compartment to rise temporarily, which can cause thawing ofsamples housed near the door of the freezer. Once the freezer is closedand the temperature decreases, the samples refreeze. This repeatedfreezing and thawing can cause more rapid degradation of samples.Keeping the freezer door open also allows frost to build up in thefreezer compartment. With repeated openings of the door, the frosteventually can freeze containers to the bottom of the freezercompartment or to each other. As a result, the door must be kept openlonger in order to break containers out of the frost, which onlyexacerbates the problem.

The increasing need for high quality bio-repositories in hospitals,research institutions, and pharmaceutical clinical research laboratoriesprovides a market for automated ultra-cold storage devices that willimprove sample quality, organize storage, provide rapid access to allspecimens, and maintain electronic records of all specimens storedwithin the container.

U.S. Pat. No. 5,921,102 to Vago, herein incorporated by reference,utilizes a storage apparatus particularly with automatic insertion andretrieval. Drawbacks of the Vago approach, but not limited thereto, arethat it fails to provide the climate control associated with the freezerand the various interchanging devices, and other features and aspects.

There is therefore a need in the art for an automated cold storageapparatus, and related method thereof, that can provide, among otherthings a more organized storage and retrieval apparatus, lessaccumulation of moisture and frost within the cold storage compartment,less temperature fluctuation from sample withdrawal, and rapid randomaccess to all specimens.

SUMMARY OF THE INVENTION

The present invention automated cold storage apparatus, and relatedmethod thereof, provides a sample process management system that is arevolutionary approach to the storage and retrieval of critical samples.The system—a significant technological breakthrough in laboratoryautomation—is the first ultra low temperature robotic system capable ofbeing validated. Samples in containers are stored and retrievedrobotically through an airlock climate-control chamber (access means)that is automatically dehumidified by a dry gas purge, such as a carbondioxide or nitrogen purge or the like. This purge rapidly reducesambient humidity to a desirable relative humidity (RH), e.g., less thanabout 15% RH, virtually eliminating the accumulation of frost.Microplates or storage containers, or the like, are systematicallyidentified using barcode technology, for example. Once through theclimate-controlled chamber, the containers (i.e., samples) arerobotically transferred to the rotary mechanism. This mechanismtransports the containers to a derived nest location upon the storagemeans, such as a carousel or one of the stationary addresses. Forillustrative purposes only, the carousel and stationary nests may have acombined capacity of 1,000 standard microplates. It is contemplated thatvarious capacities may be designed.

The preferred embodiments of the present invention automated storage andretrieval apparatus, and related method thereof, operate at an ultra lowtemperature of about −50° C. to about −90° C. It should be understoodthat the apparatus may operate in a range of −50° C. up to ambienttemperature or greater. The normal design operating temperature of thefreezer compartment of the present invention is about −80° C. It shouldbe noted that the present invention is contemplated to operate atconditions colder than ultra low temperatures in the range of about−140° C. to about −90° C. Conveniently, if the freezer fails forwhatever reason—maintenance or scheduled outage—then liquid carbondioxide can be pumped into the system and keep it at approximately −78°C. The ultra low freezer set point (approximately 78° C.) of theapparatus can be backed up by installing a cylinder of liquid carbondioxide.

In one aspect, the present invention features an automated storage andretrieval apparatus for storing containers at ultra low temperatures orother preferred temperatures. The apparatus comprising: a freezercompartment, the freezer compartment having a side wall; a storagecarousel disposed inside the freezer compartment for holding thecontainers; a climate-controlled chamber disposed on the side wall; aclimate system for controlling the climate of the chamber; and aninterchange mechanism configured. The interchange mechanism isconfigured to: interchange a container between the interchange mechanismand the climate-controlled chamber while in a chamber exchange position,and interchange a container between the interchange mechanism and thecarousel while in a carousel exchange position. The chamber also beingconfigured to: isolate the container from the interchange mechanism ascontainer is deposited from the exterior or placed into the exterior,and isolate the container from the exterior as container is exchangedbetween the chamber and the interchange mechanism.

In some embodiments, the carousel can be replaced with a stationarystorage rack, and additional storage racks may be added. The interchangemechanism is configured to interchange a container between theinterchange mechanism and the rack(s) while in a rack exchangeposition(s).

In a second aspect, the present invention provides an automated storageand retrieval apparatus for storing containers at ultra low temperaturesor other preferred temperatures. The apparatus comprising: a freezermeans for freezing the containers; a storage means disposed inside thefreezer means for holding the containers; a chamber means forinterchanging the containers between the exterior and the freezer means;a climate system control means for controlling the climate of thechamber means; and an interchange means. The interchange means for:interchanging a container between the interchange means and the chambermeans while in a chamber exchange position, and interchanging acontainer between the interchange means and the storage means while in astorage exchange position. The chamber means for: isolating thecontainer from the interchange means as container is deposited from theexterior or placed into the exterior, and isolating the container fromthe exterior as container is exchanged between the chamber means andsaid interchange means.

In a third aspect, the present invention provides a method forautomatically depositing and storing containers, as well as a method forstoring and retrieving containers in a freezer compartment of anautomated apparatus. The apparatus comprising: a freezer means forfreezing the containers; a storage means disposed inside the freezermeans for holding the containers; a chamber means for interchanging thecontainers between the exterior and the freezer means; a climate systemcontrol means for controlling the climate of the chamber means; and aninterchange means. The interchange means for: interchanging a containerbetween the interchange means and the chamber means while in a chamberexchange position, and interchanging a container between the interchangemeans and the storage means while in a storage exchange position. Thechamber means for: isolating the container from the interchange means ascontainer is deposited from the exterior or placed into the exterior,and isolating the container from the exterior as container is exchangedbetween the chamber means and said interchange means.

An advantage of the present invention automated storage and retrievalapparatus for ultra low temperature freezers, and related methodthereof, is that the apparatus can operate in a stand-alone mode or canbe integrated into a completely automated laboratory. It is scalable tomeet the needs of small laboratories as well as large institutions thatwill require long-term storage of large numbers of samples.

Another advantage of the present invention is that the apparatus can bedesigned as a slide-in unit for existing ultra-cold freezers, which willkeep the majority of the hardware in the door so as to be insulated fromthe freezer compartment, minimizing both the number of low-temperaturehardware components and the actual alteration to the freezer itself. Areduced number of moving components is continuously exposed to thedesign temperature of about −80° C., reducing the cost of production.

Further advantages of the present invention are attributed to theimproved sample quality, lowered operating costs, and reducedmaintenance of the automated storage and retrieval apparatus.

Finally, an advantage of the present invention is that it providesultra-low temperature automation or lower and user-friendly informationtechnology in a proven reliable manner.

These and other objects, along with advantages and features of theinvention disclosed herein, will be made more apparent from thedescription, drawings and claims that follow.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other objects, features and advantages of the presentinvention, as well as the invention itself, will be more fullyunderstood from the following description of preferred embodiments, whenread together with the accompanying drawings, in which:

FIG. 1 shows a schematic plan view of the automated storage andretrieval apparatus.

FIG. 2A shows a schematic perspective view of the automated storage andretrieval apparatus.

FIG. 2B shows a perspective partial view of the door or wall of acompartment and/or housing.

FIG. 3 shows a schematic cross-sectional view of the climate controlledchamber with the exterior door in open and closed positions.

FIGS. 4A and 4B show a schematic frontal view and plan view,respectively, of the related translation mechanisms of the climatecontrolled chamber.

FIGS. 5A-5D show a schematic representation of select positions of therotational alignment of the interchange mechanism.

FIGS. 6A and 6B comprise a flow chart illustrating the operation fordepositing and storing a storage container or the like in the automatedstorage and retrieval apparatus.

FIGS. 7A and 7B comprise a flow chart illustrating the operation forretrieving the targeted or desired storage container or the like in theautomated storage and retrieval apparatus.

FIG. 8 shows a schematic perspective view of the storage carousel of theautomated storage and retrieval apparatus. FIG. 9 shows a perspectiveview of an individual vertical rack from the carousel of FIG. 8,comprised of a plurality of storage trays,

FIGS. 10A and 10B show a schematic perspective view of the storage traysand their related cooperation with the vertical supports of thecarousel.

FIGS. 11A and 11B are schematic perspective views of the interchangemechanism and related components.

FIG. 12 shows a schematic block diagram of the general features of thecontrol system of the automated storage and retrieval apparatus.

FIG. 13 shows a schematic block diagram of an exemplary computer systemassociated with an embodiment of the automated storage and retrievalapparatus.

FIGS. 14A and 14B show schematic perspective views of an alternativeembodiment of the automated storage and retrieval apparatus.

FIGS. 15A-15D show schematic plan views of an alternative embodiment ofthe automated storage and retrieval apparatus providing expanded networksystem of cooperating freezer apparatuses.

FIG. 16A and 16B show schematic perspective front/exterior views of thehousing of the climate control chamber with related components in boththe closed and open position, respectively.

FIG. 17A and 17B show schematic perspective back/interior views of thehousing of the climate control chamber with related components in boththe closed and open position, respectively.

DETAILED DESCRIPTION OF THE INVENTION

Turning now to the drawings, the present invention is schematicallyshown in the plan view of FIG. 1 and perspective view of FIG. 2A, whichincludes an automated storage and retrieval apparatus 1 having one ormore storage carousels 20 disposed in a freezer compartment 10, with oneor more optional stationary racks 26, 27, an interchange mechanism 40,and a climate controlled chamber 60 that is generally disposed on a wall11 of the freezer compartment 10 or associated housing 2. A centralcontrol system 80 is coupled to the storage carousel 20, interchangemechanism 40, and climate controlled chamber 60 for controlling theiroperations. Generally, the control system 80 controls the operation ofthe apparatus so that the containers can be loaded from the exteriorinto the climate-controlled chamber 60 for retrieval by the interchangemechanism 40 for insertion onto the carousel 20 in the freezercompartment 10. Stored containers subsequently can be retrieved from thecarousel 20 by the interchange mechanism 40 and available to be takenaway to the exterior through the climate controlled chamber 60.

FIG. 2B shows a perspective partial view of the wall 11 of thecompartment and/or door of the housing. Mounted on the wall 11 are theclimate-controlled chamber 60 and a touch screen interface 82. As willbe discussed later, it is envisioned that a control system and computersystem can be accessed directly by using the touch screen interface 82and/or remotely by a stand-alone personal computer or with a local areanetwork (LAN).

Next, details of the climate controlled chamber 60 will be provided, asbest shown in FIGS. 3 and 4A-4B. A particularly desirable feature isthat the climate-controlled chamber 60 prevents ambient, humid air fromentering the interior of freezer compartment 10 during storage containerinsertion and retrieval. The Chamber 60 has an interior door 61 to allowcommunication between freezer compartment 10 and chamber 60, and anexterior door 62 to allow communication between the exterior environment(or adjacent area)and chamber 60. The chamber 60 has a climate controlsystem 66 that provides an air purging capability to cool and dehumidifythe air in the chamber 60 before interior door 61 is opened. A scanningreader device 65, preferably a barcode reader, is situated in thechamber 60 to identify storage containers as they are inserted into andretrieved from chamber 60. Information relative to the storagecontainers is transmitted from reader device 65 to central and/or remoteprocessor.

Still referring to FIGS. 3 and 4A-4B, the storage containers 3 arecarried by a transport tray 63 that is slidably mounted on two channels67, 68. The transport tray 63 can transport the container 3 to theexterior as the exterior door 62 is open, as indicated by the dashedlines. Alternatively, the transport tray 63 can transport the container3 to the interior of the freezer compartment 10 as the interior door 61is open, as indicated by the dotted lines. In one embodiment, theinterior door 61 may slide open and close on a track (not shown). Aclimate control system 66 is in communication with the chamber 60 thatdehumidifies and cools the chamber 60 while the container is isolatedtherein, i.e., both exterior and interior doors are closed. The climatecontrol system 66 includes a dry gas or dry air purge (i.e., nitrogen,carbon dioxide, or the like), that rapidly reduces ambient humidity toany desired level, e.g., less than about 25% relative humidity (RH) andas low as about 1% RH. In fact, any compressed gas from which moisturehas been removed will reduce the humidity in the airlock, and will coolthe airlock by adiabatic expansion to about −10° .C to about 0° C., oras desired.

A preferred embodiments of the present invention automated storage andretrieval apparatus, and related method thereof, operate at an ultra lowtemperature from about −50° C. to about −90° C. It should be understoodthat the apparatus may operate in a range of −50° C. up to ambienttemperature or greater. The normal design operating temperature of thefreezer compartment of the present invention is about −80° C. It shouldbe noted that the present invention is contemplated to operate atconditions colder than ultra low temperatures in the range of about−140° C. to about −90° C. Conveniently, if the freezer fails forwhatever reason—maintenance or scheduled outage—then liquid carbondioxide can be pumped into the system and keep it at approximately −78°C. Thus, the ultra low freezer-set point of the apparatus can be backedup by installing a cylinder of liquid carbon dioxide.

One skilled in the art would appreciate that various types andsubstitutes for interior and exterior chamber doors can be used.Moreover, a single door can be utilized which can rotate betweeninterior and exterior sides.

Additional details pertaining to the climate controlled chamber 60 willbe provided, as best shown in the perspective views of FIGS. 16A-16B andFIGS. 17A-17B. The front/exterior view and the back/interior view ofclimate controlled chamber 60 are shown in FIGS. 16A-16B and FIGS.17A-17B, respectively. Referring to front/exterior view of FIG. 16A, thechamber 60 includes a chamber housing 91 having its exterior door 62 ina closed position with a deep well micro-plate 92 placed thereon thetransport tray 63. It should be appreciated that a shallow wellmicro-plate may be used, as well as any other size, type, or number ofcontainers, which can be accommodated for storage and interchange. Alsoshown is a tray-motor and gear box housing 93, reading device 65, andair purge port 94. FIG. 16B shows the chamber 60 having its exteriordoor 62 in an open position.

Referring to the back/interior view of FIGS. 17A-17B, there is shown thechamber 60 including an interior door-motor gear and motor housing 95and lead screw 96, and having its interior door 61 in a closed position.FIG. 17B shows the chamber 60 having its interior door 61 in an openposition with the deep well micro-plate 92 placed thereon the transporttray 63.

Additional details of the cooperation between the freezer compartment10, carousel 20, stationary racks 26, 27, interchange mechanism 40, andclimate-controlled chamber 60 are schematically shown referring to FIGS.5A-5D. The interchange mechanism 40 is configured to interchangecontainers between it and the carousel 20 (See FIG. 5B), stationarystorage racks 26, 27 (See FIGS. 5C-5D, respectively), and theclimate-controlled compartment 60 (See FIG. 5A). Various storage meansbesides the disclosed carousels or stationary racks are contemplated,such storage means include the following but are not limited theretoautomated stackers, and with possible additional hardware, rectangulararrays of storage nests (or any predetermined shaped carousel/rackincluding linear, oval, pentagonal, hexagonal, etc.). The interchangemechanism 40 requires a picking mechanism 41 for horizontallytranslating the interchange tray 44 for interchanging the container 3with the carousel 20 or the climate controlled chamber 60. Variouspicking mechanisms include, but not limited thereto lead screws, pickingdevices, vacuum devices, side gripping fingers, vertical pincers, andconveyors. The interchange mechanism 40 further comprises a verticaltransporter 42 configured to allow the interchange mechanism 40 to betranslated vertically over a plurality of discrete heights. Variousvertical transporters include, but not limited thereto lead screws,chain drives, and conveyors. Further yet, the interchange mechanism 40comprises a rotary transporter 43 that is configured to rotate theinterchange mechanism 60 to a plurality of discrete circumferentialpositions. Various rotary mechanisms include, but not limited theretolead screws, pivot devices, gear drives, belt or chain drives, pneumaticor hydraulic devices, and conveyors.

With regards to control operations, the present invention automation androbotic motions described herein are provided in part by the controlsystem 80 and processor 81. It should be noted that the followingexemplary sequences of operations may be varied, partially omitted,overlapped to reduce the total elapsed time of operation, or reorderedin an alternative sequence.

Operation for depositing 600 a storage container is provided in theflowchart of FIGS. 6A-6B. In a first step, 601, the exterior door 62opens and transport tray 63 exits, and storage container 3 is placed inchamber 60. In step 602, the exterior door 62 closes, transport tray 63returns to chamber 60 and storage container's barcode is scanned byreader device 65, and storage location is assigned. In step 603,exterior door 60 and interior door 61 are in closed position while airpurging system 66 cools and dehumidifies air in the chamber 60. In step604, the interior door 61 opens, the transport tray 63 transports thecontainer 3 inward, a picking mechanism 43 is advanced into the chamber60 to pick up the storage containers and then retracts to place thecontainer 3 on interchange tray 44, and the interior door closes. Instep 605, the storage carousel 20 is rotated to rotationally align thecorrect vertical rack 23 with the future position of the interchangemechanism 40. In step 606, the interchange mechanism 40 is actuatedvertically by a vertical transporter 42 to vertically align with correctheight of targeted storage tray 28. In step 607, a rotary transporter 43rotates the interchange mechanism 40 to rotationally align with correctvertical rack 23. In step 608, the picking mechanism 43 is advancedsubstantially horizontally to place the storage container 3 on storagetray 28. In step 609, the picking mechanism 43 is vertically lowered adesired nominal distance, e.g., approximately ⅛-inch, and retractedsubstantially horizontally to disengage the storage container 3. In step610, the processor records relevant storage container information in thedatabase. In step 611, provided no other activity is required at thestorage carousel 20 (or at any stationary storage rack 26, 27) theinterchange mechanism 40 is rotated to rotationally align with interiordoor 61 of the chamber 60 and the interchange mechanism 60 is verticallyactuated to vertically align with interior door 61, for a resting state.It should be noted that a similar process and aspect applies to thestationary racks 26, 27, except that the racks do not rotate.

Next, the operation for retrieving 700 the desired or targetedcontainers 3 from the storage trays 28, is provided in the flowchart ofFIGS. 7A-7B. In a first step 701, a storage container identification(ID) for a desired or targeted container is entered electronically orvia data input device such a display panel integral with the apparatushousing or a remote there from, both of which being operativelyconnected to the control system 80. In step 702, a central processor 81locates relevant storage container information in the database andlocation of storage container in storage carousel 20 (or stationarystorage racks) is determined. Optionally, step 703, if security isrequired, then an access code is entered via data input device such adisplay panel integral with the apparatus housing or a remote processor,and confirmed by central processor 81 to allow access to the desiredstorage container 3. In step 704, the storage carousel 20 is rotated torotationally align the correct vertical rack 23, containing the desiredstorage container 3, with the future position of the interchangemechanism 40. In step 705, the interchange mechanism 40 is actuatedvertically by a vertical transporter 42 to vertically align with thecorrect height of a desired storage tray 28. In step 706, the rotarytransporter 43 rotates the interchange mechanism 40 to rotationallyalign with correct vertical rack 23. In step 707, the picking mechanism43 is advanced substantially horizontally to retrieve the storagecontainer 3 from storage tray 28. In step 708, the picking mechanism 43is vertically raised a desired nominal distance, e.g., approximately⅛-inch, and retracted horizontally to engage and withdraw the storagecontainer 3. In step 709, the interchange mechanism 40 is rotated torotationally align with interior door 61 of chamber 60. In step 710, theexterior door 62 and interior door 61 are in closed positions while airpurging system 66 cools and dehumidifies air in chamber 60. In step 711,the interior door 61 opens, the transport tray 63 extends as the pickingmechanism 43, advancing into chamber 60 to disengage the storagecontainer in the chamber 60. In step 712, the picking mechanismwithdraws into the freezer compartment and the interior door 61 closes,and the reader device 65 reads the barcode ID of the storage containerto confirm that it matches the ID that was entered in step 701 of thepresent invention retrieval process. In step 713, the exterior door 62opens, allowing access to the storage container 3. It should be notedthat a similar process and aspect applies to the stationary racks 26,27, except that the racks do not rotate.

Next, details pertaining to the storage carousel 20 will be discussed,as schematically shown in FIGS. 8-9. The perspective view as shown inFIG. 8 includes a carousel 20 having some racks 23 omitted forillustration purposes. The carousel 20 comprises an annular ring ofvertical racks 23 arranged circumferentially between an upper horizontalplate 29 (shown in dashed lines) and a lower horizontal plate 30. Thecarousel may be various sizes, dimensions, and shapes, including linear,rectangular, pentagonal, and hexagonal or the like. A base plate 31,acts as a bearing brace to the support storage carousel 20 whileallowing rotation of carousel 20 about the vertical axis. Rotation ofcarousel 20 is actuated by a motor driveshaft 32, which runs throughlower horizontal plate 30 and base plate 31 to communicate with a motor(not shown). The motor is preferably mounted beneath the floor offreezer compartment 10, where the refrigeration equipment is housed, andwhere the motor is not exposed to the ultra-cold temperatures of freezercompartment 10. Storage carousel 20 may rest on a ball bearing system toprovide reduced friction at ultra-cold temperatures. Theself-lubricating bearing system, e.g., graphite ceramic, may be used aswell as other types known to those skilled in the art. Vertical racks 23are mounted to upper horizontal plate 29 and lower horizontal plate 30with right-angle braces or the like. The vertical racks 23 comprise avertical support 33 and a plurality of adjustable storage trays 28 tohold a plurality of storage containers 3, which could be of standard orvarying size.

FIG. 9 is a perspective view of an individual vertical rack 23,comprised of a plurality of storage trays 28.

Next, details pertaining to the storage trays 28 and cooperation withthe vertical support 33 of the carousel 20 will be discussed, as bestshown in FIGS. 10A-10B. Storage trays 28 have a flat, horizontallyoriented support surface 34 with an open center 35 to allow theinterchange mechanism 40 to engage the storage containers 3 either forplacement onto storage tray 28 or for retrieval from storage tray 28.The storage trays 28 have a flat vertically oriented attachment surface36 positioned at a right angle to the proximal edge of storage trays 28,which allows connection of storage trays 28 to vertical support 33 ofthe vertical racks 23 by an attachment assembly 37 (partially shown).Other configurations of the attachment assembly 37 are contemplatedaccording to the type of interactions between the various components andsubsystems. The distal edge of storage trays 28 is open and outwardfacing to allow access to the storage containers. Other configurationsof the storage trays 28 are contemplated according to the type ofinteractions between the various components and subsystems. Verticallyoriented raised guides 38 are situated on lateral edges of storage trays28 to prevent storage containers from becoming misaligned on storagetrays 28. The raised guides 38 can be stamped out of the surface ofstorage trays 28, or other suitable means known to those skilled in theart.

Next, details of an exemplary embodiment of the interchange mechanism 40will be discussed, as best shown in FIGS. 11A-11B. In this particularembodiment the interchange mechanism 40 comprises a pair of guide rails45 and 46 that are located with their axes vertically within the freezercompartment 10 and they extend for a substantial length as required bythe discrete heights of the various interchange operations. The guiderails 45 and 46 are slidably mounted on the interchange plate 47. Avertical lead screw 48 having an axis length-wise within the freezercompartment 10 is actuated by a motor 53, located below the freezercompartment, for vertically translating the interchange plate 47 to adesired height. A vertically mounted rotating square shaft 49 is drivenby a motor 54 mounted beneath the floor of freezer compartment 10. Thesquare shaft 49 drives the interchange tray 44 using a gear train, suchas the square shaft gear 50 and tray gear 51, as shown. The drive gearmates with a rack 52 in communication with the interchange tray 44.During operation, the square shaft 49 rotates in a clockwise directionto drive the gear train and rack 52, thereby driving the interchangetray 44 horizontally into an extended position, as shown by the dashedlines. While in the extended position, the interchange tray 44 iscapable of retrieving or dropping off a container. Next, the squareshaft 49 rotates in a counter-clockwise direction to drive the geartrain and rack 52 in an opposite direction, causing the rack 52 andinterchange tray 44 to retract to a rest position. The rotarytransporter 43, driven by a motor (not shown) mounted beneath the floorof the freezer compartment 10, rotates the interchange mechanism 40 torotationally align with correct vertical rack 23 or stationary storagerack 26, 26, and interior door 61 of the chamber 60, or any otherposition as required. The rotary transporter 43 may be pivoted, rotated,or translated using a means known to those skilled in the art.

It should be noted that the motors for the storage carousel 10, verticaltransporter 42, rotary transporter 43, picking mechanism 42, andtransport tray 63 can be a variety of types of motors known to thoseskilled in the art, including but not limited thereto servo motors andstepper motors, or any direct current (DC) motor with suitable positionor velocity controllers. In the various preferred embodiments disclosedherein, the motors are mounted outside of the freezer compartment 10 toextend the life of the component and improve the overall serviceabilityof the apparatus. With the exception of the transport tray 63 the driveshafts are mounted through a series of sophisticated thermal seals andthermal couplers designed to maintain temperature stability throughoutall operating cycles. In a choice embodiment, the servomotors may be ofa SMART MOTOR by Antimatics, Corp. These type of servo motors aremicroprocessor controlled, ensuring accurate placement and monitoring ofthe robotics operating within the critical environment; however, anyposition or velocity controlled motors may be used.

Next, the general features of the present invention control system 1280will be discussed, as shown in the block diagram of FIG. 12. The controlsystem 1280 interfaces with a computer system 1281 that may be integralwith the housing 2 or remote via a wire or wireless communication, orany combination thereof. Moreover, the control system 1280 may be incommunication with and integrated with a laboratory informationmanagement system (LIMS) 1282. The control system 1280 is operativelyconnected with the various motors 1283, actuators 1284, position sensors1285, and identification sensors 1286. It is contemplated that that theinformation derived from the sample or work pieces carried in thecontainers 3 while practicing the present invention will provide aninformation technology platform for the user. The computer system 1281is intended to be a user-friendly, utilizing Windows-based platform orany other operating system, and may be integrated with a variety oflaboratory information management systems. It is envisioned that thecontrol system 1280 and computer system 1281 can be accessed directly byusing a touch screen interface or remotely by a stand alone personalcomputer or with a local area network (LAN).

The present invention apparatus provides the user the capability, amongother things, to set top-level user-definable parameters to controlcontainer (sample) access based on research groups, research campaignsor individual laboratories. For instance, sample data can be configuredby the user to meet the user's particular research requirements. Thedatabase can then search the user'1s sample populations to find all thesamples that match the user's requested research parameters. Moreover,time/temperature profiles and sample access histories are maintainedcontinuously. The present invention allows the user to set samplemigration thresholds. This feature, employing sample usage frequencies,prompts the movement of low demand samples into longer-term storageunits—maximizing the efficiency of the user's sample process managementsystem. Furthermore, the present invention apparatus enables the user togenerate a variety of reports in support of the user's quality assuranceneeds. Finally, the user will benefit from the present invention'sinformation technology by receiving excellent sample security, optimalsample visibility, optimal quality assurance, sample migration controland flexible data management.

Next, exemplary embodiments of the control system and computer systemwill be discussed, as best shown in FIG. 13. The controls and processingof present invention may be implemented using hardware, software or acombination thereof and may be implemented in one or more computersystems or other processing systems, such as personal digit assistants(PDAs). In an example embodiment, the invention was implemented insoftware running on a general purpose computer 1300 as illustrated inFIG. 1300. Computer system 1300 includes one or more processors, such asprocessor 1304. Processor 1304 is connected to a communicationinfrastructure 1306 (e.g., a communications bus, cross-over bar, ornetwork). Computer system 1300 includes a display interface 1302 thatforwards graphics, text, and other data from the communicationinfrastructure 1306 (or from a frame buffer not shown) for display onthe display unit 1330.

Computer system 1300 also includes a main memory 1308, preferably randomaccess memory (RAM), and may also include a secondary memory 1310. Thesecondary memory 1320 may include, for example, a hard disk drive 1312and/or a removable storage drive 1314, representing a floppy disk drive,a magnetic tape drive, an optical disk drive, etc. The removable storagedrive 1314 reads from and/or writes to a removable storage unit 1318 ina well known manner. Removable storage unit 1318, represents a floppydisk, magnetic tape, optical disk, etc. which is read by and written toby removable storage drive 1314. As will be appreciated, the removablestorage unit 1318 includes a computer usable storage medium havingstored therein computer software and/or data.

In alternative embodiments, secondary memory 1310 may include othermeans for allowing computer programs or other instructions to be loadedinto computer system 1300. Such means may include, for example, aremovable storage unit 1322 and an interface 1320. Examples of suchremovable storage units/interfaces include a program cartridge andcartridge interface (such as that found in video game devices), aremovable memory chip (such as a ROM, PROM, EPROM or EEPROM) andassociated socket, and other removable storage units 1322 and interfaces1320 which allow software and data to be transferred from the removablestorage unit 1322 to computer system 1300.

Computer system 1300 may also include a communications interface 1324.Communications interface 1324 allows software and data to be transferredbetween computer system 1300 and external devices. Examples ofcommunications interface 1324 may include a modem, a network interface(such as an Ethernet card), a communications port, a PCMCIA slot andcard, etc. Software and data transferred via communications interface1324 are in the form of signals 1328, which may be electronic,electromagnetic, optical or other signals capable of being received bycommunications interface 1324. Signals 1328 are provided tocommunications interface 1324 via a communications path (i.e., channel)1326. A channel 1326 (or any other communication means or channeldisclosed herein) carries signals 1328 and may be implemented using wireor cable, fiber optics, a phone line, a cellular phone link, an RF linkand other communications channels.

In this document, the terms “computer program medium” and “computerusable medium” are used to generally refer to media such as removablestorage drive 1314, a hard disk installed in hard disk drive 1312, andsignals 1328. These computer program products are means for providingsoftware to computer system 1300. The invention includes such computerprogram products.

Computer programs (also called computer control logic) are stored inmain memory 1308 and/or secondary memory 1310. Computer programs mayalso be received via communications interface 1324. Such computerprograms, when executed, enable computer system 1300 to perform thefeatures of the present invention as discussed herein. In particular,the computer programs, when executed, enable processor 1304 to performthe functions of the present invention. Accordingly, such computerprograms represent controllers of computer system 1300.

In an embodiment where the invention is implemented using software, thesoftware may be stored in a computer program product and loaded intocomputer system 1300 using removable storage drive 1314, hard drive 1312or communications interface 1324. The control logic (software), whenexecuted by the processor 1304, causes the processor 1304 to perform thefunctions of the invention as described herein.

In another embodiment, the invention is implemented primarily inhardware using, for example, hardware components such as applicationspecific integrated circuits (ASICs). Implementation of the hardwarestate machine to perform the functions described herein will be apparentto persons skilled in the relevant art(s).

In yet another embodiment, the invention is implemented using acombination of both hardware and software.

In an example software embodiment of the invention, the methodsdescribed above were implemented in VISUAL BASIC control language, butcould be implemented in other programs such as, but not limited to, C++programming language.

Next, details of an alternative second embodiment of the presentinvention will be discussed, as best shown in FIGS. 14A-B. The storagecarousel is fixed in place (i.e., no rotation) providing a fixed hotel1420. The storage containers 1403 are accommodated on shelves 1428 inthe same manner as in the storage carousel. However, the interchangemechanism 1440 is located in the central core 1439 of the fixed hotel1420. The interchange mechanism 1440 includes an interchange tray 1444,and may rotate about its axis and travel vertically as previouslydiscussed herein. The interchange mechanism 1440 retrieves storagecontainers from shelves, takes them to a vertical position aligned withan access portal 1437, and moves them through the portal 1437 to theexterior of the freezer via the climate controlled chamber 1460. It isnoted that the access portal 1437 is a fixed hole in the fixed hotel1420 allowing samples to access the interchange mechanism 1440. One ormore access portals may be used if one wishes to mate several fixedhotels 1420 or rotating carousels together, or provide more than onepoint of access portal 1437. Furthermore, the access portal may bemovable if one wishes to provide rotational movement to one “slice” ofthe hotel 1420.

An advantage of this second embodiment approach, but not limited theretois that it may be accommodated in a cylindrical freezer compartment,occupying less space. In addition, this apparatus and method obviatesthe need for a rotational mechanism for the carousel (unless one wishesto have a movable access port). All other aspects of the design are thesame as previously described above.

In addition, as a third alternative embodiment, one could also have asecond carousel outside the one depicted in FIGS. 14A-14B, so as toallow for greater storage space. In this embodiment the inside carouselcould rotate so as to allow a vertical arrangement and rotationalalignment of access ports to access any compartment in the outercarousel.

Next, details of providing an expanded network system of cooperatingfreezer apparatuses 1501 will be discussed, as best shown n FIGS. 15A-D.The plurality storage of carousels 1520 (or stationary storage racks1526, 1527 and fixed hotels), interchange mechanism 1540, and climatecontrol chamber 1560 operate with the methods and aspects describedherein. The plurality of storage carousels 1520 (stationary racks orfixed hotels) operates in an enclosure 1502. The enclosure 1502 may beequipment housing-type as previously discussed to accommodate a freezerunit or plurality of freezer units. Alternatively, the enclosure 1502may be an entire room, or a plurality of rooms, as disclosed in the U.S.Pat. No. 5,921,102 Vago patent. The configurations shown in FIGS. 15A-Dare illustrative in nature and are not intended to be exhaustive asother combinations and designs are contemplated. Essentially, thecontainers 1503 are interchanged, stored, deposited, and retrieved amongthe storage carousels 1520 (including stationary storage racks 1526,1527), interchange mechanism 1540, and climate-controlled chamber 1560using the aspects and methods previously disclosed herein, whilerecognizing the enclosure 1502 may be a room or equipment housing, orany combination thereof. A control system 1580 is operatively connectedto the various components and subsystems, wherein the controls andprocessor are locally or remotely located.

The interchange mechanism 1540 cooperate with multiple locationsallowing containers 1503 to pass among carousels 1520 and stationaryracks 1526, 1527, and of course the climate-controlled chamber 1560. Asshown in FIGS. 15C-D, to accomplish this task, a translating mechanism1590 is provided to translate or shift the interchange mechanism 1540 tothe target carousel(s) 1520 or stationary racks 1526,1527. Various meansare contemplated for translating the interchange mechanism 1540,including but not limited thereto, track devices, wheels, conveyors,pulleys, suspension devices, belts, gears, or other robotic devices.

Some advantages of the present invention automated storage and retrievalapparatus for ultra low temperature freezers, and related methodthereof, are that it provides a more organized storage and retrievalapparatus, less accumulation of moisture and frost within the coldstorage compartment, less temperature fluctuation from samplewithdrawal, and rapid random access to all specimens.

Moreover, another advantage of the present invention is that theapparatus can operate in a stand-alone mode or can be integrated into acompletely automated laboratory. It is scalable to meet the needs ofsmall laboratories as well as large institutions that will requirelong-term storage of large numbers of samples.

Another advantage of the present invention is that the apparatus can bedesigned as a slide-in unit for existing ultra-cold freezers, which willkeep the majority of the hardware in the door so as to be insulated fromthe freezer compartment, minimizing both the number of low-temperaturehardware components and the actual alteration to the freezer itself. Areduced number of moving component is continuously exposed to the normaldesign temperature of about −80° C., reducing the cost of production.

Further advantages of the present invention are attributed to theimproved sample quality, lowered operating costs, and reducedmaintenance of the automated storage and retrieval apparatus.

Still further, an advantage of the present invention is that theclimate-controlled chamber prevents ambient, humid air from entering theinterior of freezer compartment during storage container insertion andretrieval.

Finally, an advantage of the present invention is that it providesultra-low temperature automation and user-friendly informationtechnology in a proven reliable manner. It is contemplated that thepresent invention apparatus may provide an operation temperature belowand above the ultra low operating temperature.

The invention may be embodied in other specific forms without departingfrom the spirit or essential characteristics thereof. The foregoingembodiments are therefore to be considered in all respects illustrativerather than limiting of the invention described herein. Scope of theinvention is this indicated by the appended claims rather than by theforegoing description, and all changes which come within the meaning andrange of equivalency of the claims are therefore intended to be embracedherein.

We claim:
 1. An automated storage and retrieval apparatus for storingcontainers at ultra low temperatures, said apparatus comprising: afreezer compartment, said freezer compartment having a side wall; astorage carousel disposed inside said freezer compartment for holdingthe containers; a climate-controlled chamber disposed on said side wall;a climate system for controlling the climate of said chamber; aninterchange mechanism configured to: interchange a container betweensaid interchange mechanism and said climate-controlled chamber while ina chamber exchange position, and interchange a container between saidinterchange mechanism and said carousel while in a carousel exchangeposition; said chamber being configured to: isolate the container fromsaid interchange mechanism as container is deposited from the exterioror placed into the exterior, and isolate the container from the exterioras container is exchanged between said chamber and said interchangemechanism; and said chamber further comprises: a transport tray slidablymounted to said chamber for transporting the container between an outerposition closest to the exterior and an interior position closest tosaid interchange mechanism.
 2. The apparatus of claim 1, wherein saidchamber further comprises: an exterior door, whereby said exterior dooris adapted to allow the containers to interchange between said chamberand the exterior, and an interior door, whereby said interior door isadapted to allow the containers to interchange between said chamber andsaid interchange mechanism.
 3. The apparatus of claim 1, wherein saidcontrolled chamber further comprises: a motor operably connected to saidtransport tray for translating said tray between the exterior positionand interior position, and any position generally there between; andsaid motor being disposed outside said freezer compartment.
 4. Theapparatus of claim 1, wherein said climate system comprises a dry gassupply to dehumidify said chamber and cool said chamber.
 5. Theapparatus of claim 1, wherein said chamber comprises a writing device.6. The apparatus of claim 1, wherein said chamber comprises a readingdevice to identify the containers as they are inserted into andretrieved from said chamber.
 7. The apparatus of claim 1, furthercomprising a control system, wherein said control system is operativelyconnected with said carousel, said interchange mechanism, and chamberfor controlling their operations.
 8. The apparatus of claim 7, whereinsaid control system comprises a processor for processing data relativeto the containers being stored in and retrieved from the apparatus. 9.The apparatus of claim 7, wherein said control system comprises aprocessor for processing data relating to contents of the containersbeing stored in and retrieved from the apparatus.
 10. The apparatus ofclaim 7, further comprising a user station operatively connected to theapparatus, said user station comprising a data input means for inputtingdata to said processor relative to the containers.
 11. The apparatus ofclaim 1, wherein said interchange mechanism further comprises: aninterchange tray configured to retain the container.
 12. The apparatusof claim 11, wherein said interchange mechanism comprises: a pickingmechanism translating said interchange tray for interchanging thecontainer with said carousel or said chamber.
 13. The apparatus of claim12, further comprises: a motor operably connected to said pickingmechanism for substantially horizontally translating said pickingmechanism between an extended position for use during the interchangingof the container, and a retracted position while the container remainsin the non-extended position; and said motor being disposed outside saidfreezer compartment.
 14. The apparatus of claim 13, wherein saidinterchange mechanism further comprises: a vertical transporterconfigured to allow said interchange mechanism to be translatedvertically over a plurality of discrete heights.
 15. The apparatus ofclaim 14, wherein said interchange mechanism further comprises: a rotarytransporter, said rotary transporter configured to rotate saidinterchange mechanism to a plurality of discrete circumferentialpositions.
 16. The apparatus of claim 15, wherein said circumferentialpositions include rotational alignment corresponding to a position atwhich the interchange mechanism can: interchange selected containerswith said climate-controlled chamber while in the chamber exchangeposition; and interchange selected containers with said carousel whilein the carousel exchange position.
 17. The apparatus of claim 15,further comprises: a motor operably connected to said rotary transporterfor rotating said interchange mechanism the plurality of discretecircumferential orientations; and said motor being disposed outside saidfreezer compartment.
 18. The apparatus of claim 14, wherein saiddiscrete heights include the heights corresponding to a height at whichthe interchange mechanism can: interchange selected containers with saidclimate-controlled chamber while in the chamber exchange position; andinterchange selected containers with said carousel while in the carouselexchange position.
 19. The apparatus of claim 14, further comprises: amotor operably connected to said vertical transporter for verticallytranslating said interchange mechanism to discrete heights; and saidmotor being disposed outside said freezer compartment.
 20. The apparatusof claim 1, wherein said carousel further comprises an annular ring ofvertical racks arranged circumferentially.
 21. The apparatus of claim20, wherein said carousel further comprises storage trays to hold aplurality of storage containers.
 22. The apparatus of claim 21, whereinsaid storage trays are adjustably mounted.
 23. The apparatus of claim20, wherein said carousel further comprises an upper horizontal topplate and a lower horizontal support plate.
 24. The apparatus of claim20, wherein said carousel is rotatable so as to align said verticalracks with said interchange mechanism.
 25. The apparatus of claim 20,further comprising: a motor operably connected to said carousel forrotating said carousel; and said motor being disposed outside saidfreezer compartment.
 26. An automated storage and retrieval apparatusfor storing containers at ultra low temperatures, said apparatuscomprising: a freezer means for freezing the containers; a storage meansdisposed inside said freezer means for holding the containers; a chambermeans for interchanging the containers between the exterior and saidfreezer means; a climate system control means for controlling theclimate of said chamber means; an interchange means for: interchanging acontainer between said interchange means and said chamber means while ina chamber exchange position, and interchanging a container between saidinterchange means and said storage means while in a storage exchangeposition; said chamber means for: isolating the container from saidinterchange means as container is deposited from the exterior or placedinto the exterior, and isolating the container from the exterior ascontainer is exchanged between said chamber means and said interchangemeans; and said chamber means comprising: a transport tray slidablymounted to said chamber means for transporting the container between anouter position closest to the exterior and an interior position closestto said interchange means.
 27. An automated storage and retrievalapparatus for storing containers at ultra low temperatures, saidapparatus comprising: a freezer compartment, said freezer compartmenthaving a side wall; a storage device disposed inside said freezercompartment for holding the containers; a climate-controlled chamberdisposed on said side wall; a climate system for controlling the climateof said chamber; an interchange mechanism configured to: interchange acontainer between said interchange mechanism and said climate-controlledchamber while in a chamber exchange position, and interchange acontainer between said interchange mechanism and said storage devicewhile in a device exchange position; said chamber being configured to:isolate the container from said interchange mechanism as container isdeposited from the exterior or placed into the exterior, and isolate thecontainer from the exterior as container is exchanged between saidchamber and said interchange mechanism; and said chamber furthercomprises: a transport tray slidably mounted to said chamber fortransporting the container between an outer position closest to theexterior and an interior position closest to said interchange mechanism.28. The apparatus of claim 27, wherein said storage device is movable soas to align said storage device with said interchange mechanism.
 29. Theapparatus of claim 27, wherein said storage device is stationary.
 30. Amethod for automatically storing and retrieving containers in a freezercompartment at ultra low temperatures, said method comprising: providinga carousel in said freezer compartment; providing a climate controlledchamber; retrieving a stored container from said freezer into saidclimate controlled chamber, while said chamber is isolated from theexterior; controlling the climate of said chamber while isolating saidchamber for a predetermined time while the container remains in saidchamber; and presenting the container for pickup while said chamber isisolated from said freezer compartment, wherein said presenting thecontainer comprises ejecting the container to the exterior for pickup.31. A method for automatically depositing and storing containers in afreezer compartment of an automated apparatus at ultra low temperatures,said apparatus comprising: a freezer compartment, said freezercompartment having a side wall; a storage carousel disposed inside saidfreezer compartment for holding the containers; a climate-controlledchamber disposed on said side wall; a climate control system forcontrolling the climate of said chamber; an interchange mechanismconfigured to: interchange a container between said interchangemechanism and said climate-controlled chamber while in a chamberexchange position, and interchange a container between said interchangemechanism and said carousel while in a carousel exchange position; saidchamber being configured to: isolate the container from said interchangemechanism as container is deposited from the exterior or placed into theexterior, and isolate the container from the exterior as container isexchanged between said chamber and said interchange mechanism; and saidchamber further comprises: a transport tray slidably mounted to saidchamber for transporting the container between an outer position closestto the exterior and an interior position closest to said interchangemechanism.
 32. A method for automatically storing and retrievingcontainers in a freezer compartment of an automated apparatus at ultralow temperatures, said apparatus comprising: a freezer compartment, saidfreezer compartment having a side wall; a storage carousel disposedinside said freezer compartment for holding the containers; aclimate-controlled chamber disposed on said side wall; a climate controlsystem for controlling the climate of said chamber; an interchangemechanism configured to: interchange a container between saidinterchange mechanism and said climate-controlled chamber while in achamber exchange position, and interchange a container between saidinterchange mechanism and said carousel while in a carousel exchangeposition; said chamber being configured to: isolate the container fromsaid interchange mechanism as container is deposited from the exterioror placed into the exterior, and isolate the container from the exterioras container is exchanged between said chamber and said interchangemechanism; and said chamber further comprises: a transport tray slidablymounted to said chamber for transporting the container between an outerposition closest to the exterior and an interior position closest tosaid interchange mechanism.
 33. A method for automatically depositingand storing containers in a freezer compartment of an automatedapparatus at ultra low temperatures, said apparatus comprising: afreezer means for freezing the containers; a storage means disposedinside said freezer means for holding the containers; a chamber meansfor interchanging the containers between the exterior and said freezermeans; a climate system control means for controlling the climate ofsaid chamber means; an interchange means for: interchanging a containerbetween said interchange means and said chamber means while in a chamberexchange position, and interchanging a container between saidinterchange means and said storage means while in a storage exchangeposition; said chamber means for: isolating the container from saidinterchange means as container is deposited from the exterior or placedinto the exterior, and isolating the container from the exterior ascontainer is exchanged between said chamber means and said interchangemeans; and said chamber means comprising: a transport tray slidablymounted to said chamber means for transporting the container between anouter position closest to the exterior and an interior position closestto said interchange means.
 34. A method for automatically storing andretrieving containers in a freezer compartment of an automated apparatusat ultra low temperatures, said apparatus comprising: a freezer meansfor freezing the containers; a storage means disposed inside saidfreezer means for holding the containers; a chamber means forinterchanging the containers between the exterior and said freezermeans; a climate system control means for controlling the climate ofsaid chamber means; an interchange means for: interchanging a containerbetween said interchange means and said chamber means while in a chamberexchange position, and interchanging a container between saidinterchange means and said storage means while in a storage exchangeposition; and said chamber means for: isolating the container from saidinterchange means as container is deposited from the exterior or placedinto the exterior, isolating the container from the exterior ascontainer is exchanged between said chamber means and said interchangemeans; and said chamber means comprising: a transport tray slidablymounted to said chamber means for transporting the container between anouter position closest to the exterior and an interior position closestto said interchange means.